• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.40 no.1
• /
• pp.69-77
• /
• 2012

After lunar explorations were restarted in 1990s, the world space advanced countries have been competing actively to preoccupy the Moon from the 2000s. Korea has been also conducting precedent study on lunar exploration to carry out that by ourselves in 2020. This study analyzed delta-V of various Earth-Moon transfer trajectories for minimization of fuel consumption. Through the simulation, the best Earth-Moon transfer trajectory for Korean lunar mission is suggested and it will be used as useful materials of Korean lunar mission.

• Current Industrial and Technological Trends in Aerospace
• /
• v.6 no.1
• /
• pp.27-34
• /
• 2008

One of the purposes of space exploration is to be able to utilize the unlimited natural resources in the universe. For this purpose, plans for lunar and mars bases have been proposed by leading nations. In order to construct bases and search for resources, it is necessary to employ and develop rovers for surface navigation and exploration. With proper knowledge about Lunar surface, technology for lunar rover development can be established without serious obstacles, since robot technology for rover development has been well prepared in Korea. In this paper, lunar rovers and mars rovers developed and planned by other countries as well as the current status of robot technology in Korea have been analyzed.

• Korean Journal of Remote Sensing
• /
• v.15 no.3
• /
• pp.167-175
• /
• 1999

So far, the remote sensing technology has widely been used in a variety of application areas such as military, medical imaging, environment, geology and so forth. The microwave remote sensing uses the wavelengths ranging from around one centimeter up to a few tens of centimeters and is known to be very effective regardless of the weather conditions and the day/night time as compared with the reflective InfraRed (IR) remote sensing or the thermal IR remote sensing. There are three generic modes of synthetic aperture radar imaging systems depending on its application, that is, stripmap mode, spotlight mode, or inverse mode. In this article we focus on the issue of imaging of flying aircrafts for the inverse mode of a ground - based, fixed radar with moving objects. The imaging of flying aircrafts is considered to be an important step for the automatic target recognition systems, and therefore a great deal of efforts have recently been made on the subject. Here we review the three representative methods including the Fourier transform processing, the time - frequency processing, and the reconstruction from the projection. Some relative merits and drawbacks are also discussed.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
• /
• 1994.07a
• /
• pp.75-91
• /
• 1994

제주도의 지하수는 상위지하수, 기저지하수, 연안용출수, 심부지하수 등으로 분류될 수 있다. 이들을 효율적으로 활용하고 또 보존, 관리하기 위하여는 탐사가 선행되어야 한다. 구성물질의 물성대비를 탐사의 원리로 하는 물리탐사는 간접적 정보를 제공한다는 점에서 조사단계에서 흔히 간과되어 왔으나, 지표 상부에서 지하 심부까지의 정보를 제공할 수 있는 유일한 탐사방법이라는 점에서 그 중요성이 재인식되어야 한다. 물리탐사는 비파괴적인 탐사방법일 뿐 아니라 날은 탐사범위를 상대적으로 짧은 기간에 탐사할 수 있는 경제성을 갖고 있기 때문에 결과적으로 조사단계에서 소요되는 총비용을 현저히 줄일 수 있기 때문이다. 필자는 여기서, 제주도의 지하수문제에 대하여 물리탐사가 담당할 수 있는 역할에 대하여 최근의 탐사실례들을 통하여 기술하고자 한다. 이들 중에는 '복합 물리탐사방법에 의한 지하수탐사', '항공원격탐사에 의한 해안 용출수탐사', '물리탐사에 의한 해수침입영역 조사' 그리고 지하수 부존과 밀접한 관련이 있는 '지질구조선 탐사' 등이 포함되어 있다. 후속의 지질조사와 시추조사에서 얻은 직접적 정보들이 물리탐사에 의한 해석에 feedback 될 수 있는 조사체계를 갖춘다면 향후 제주도의 지하수와 관련한 문제에 물리탐사가 보다 효과적으로 사용될 수 있을 것임을 강조한다.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.44 no.8
• /
• pp.741-757
• /
• 2016

Over 60 years has passed since mankinds started space exploration beyond the Earth with lunar explorer Luna 1 launched by Soviet Union. Unprecedently remarkable outcomes have been obtained by sending unmanned spacecrafts to most planets in the solar system and having the lander landed on the approaching comet toward the Earth even though any evidence of life presence has not been discovered yet. Only moon is an natural object beyond the earth on which human beings landed. Many countries are planning to send humans to the moon or mars to build colonies and to survive with substantiality. Korean lunar exploration program has officially started as of 2016 after its plan including lunar exploration has been specified in the series of National Space Promotion Plan since Korea initiated space development in early 1990s. In this paper, the plan for Korean space exploration is summarized with reviewing overseas space exploration program status and trends.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.39 no.1
• /
• pp.42-49
• /
• 2011

Telemetry link requires high data rate to transmit the multimedia data for lunar explorations in space communications. In this paper, we analyze a data rate with the modulation and channel coding schemes based on Consultative Committee for Space Data Systems (CCSDS) in S, X, Ku and Ka bands, respectively. Then, we suggests modulation and channel coding schemes to meet the link margins and have a maximum data rate for lunar explorations in telemetry links.

• Current Industrial and Technological Trends in Aerospace
• /
• v.5 no.1
• /
• pp.3-11
• /
• 2007

1990년대 초부터 2000년대 중반까지 구소련의 붕괴와 예산 투자의 저조로 정체기에 접어들었던 우주개발은 달 및 행성탐사와 같은 새로운 연구개발 움직임과 중국, 인도 등 새로운 우주강자의 부상으로 현재 신성장기를 맞이하고 있는 것으로 보인다. 전 세계 우주프로그램의 정부투자도 2006년 총 50.36 십억 달러로 역사상 최고점을 기록하고 있기도 하다. 주요 우주개발국들은 미국의 우주탐사 계획에 버금가는 탐사계획들을 잇따라 발표했으며, GPS, GLONASS, Galileo 등 위성항법 분야 연구개발에도 높은 우선순위를 부여하고 있다. 정부의 연구개발 투자 확대는 우주산업의 활성화에 직접적으로 영향을 미치는 요인이 된다. 실제로 미국 우주산업 매출의 90%가, 그리고 유럽 우주산업 매출의 60%가 정부고객으로부터 발생하고 있다. 2005년 우주산업 매출은 총 88.8 십억 달러로 전년대비 6% 정도 성장하였으며, 여전히 위성서비스 분야가 전체 매출에서 차지하는 비중이 60%로 가장 높다. 본고에서는 우주분야의 정부 예산 투자 현황과 우주탐사 및 위성항법을 중심으로 한 새로운 연구개발 움직임을 국가별로 살펴보고, 우주산업의 동향과 전망, 그리고 우리나라의 우주산업과 우주개발 관련 주요 정책변화, 현재 진행 중인 국가 우주개발 프로그램에 대해 간략하게 살펴보도록 하겠다.

• 한국지구물리탐사학회:학술대회논문집
• /
• 2011.10a
• /
• pp.25- 26
• /
• 2011

• 한국지구물리탐사학회:학술대회논문집
• /
• 2010.10a
• /
• pp.151-152
• /
• 2010

• Geophysics and Geophysical Exploration
• /
• v.25 no.1
• /
• pp.26-37
• /
• 2022

Recently, multiple methods using small aircraft for geophysical exploration have been suggested as a result of the development of information and communication technology. In this study, we introduce the hybrid unmanned aircraft electromagnetic system of the Korea Institute of Geosciences and Mineral resources, which is under development. Additionally, data processing and interpretation methods are suggested via the analysis of datasets obtained using the system under development to verify the system. Because the system uses a three-component receiver hanging from a drone, the effects of rotation on the obtained data are significant and were therefore corrected using a rotation matrix. During the survey, the heights of the source and the receiver and their offsets vary in real time and the measured data are contaminated with noise. The noise makes it difficult to interpret the data using the conventional method. Therefore, we developed a recurrent neural network (RNN) model to enable rapid predictions of the apparent resistivity using magnetic field data. Field data noise is included in the training datasets of the RNN model to improve its performance on noise-contaminated field data. Compared with the results of the electrical resistivity survey, the trained RNN model predicted similar apparent resistivities for the test field dataset.